A substrate transfer device for a processing system for processing a substrate such as a semiconductor substrate or the like is provided with a chamber, a table and a transfer mechanism. The table is housed within the chamber and is moved within the chamber by the transfer mechanism of a linear motor.
The substrate transfer device is provided with a linear scale and a sensor in order to measure the position of the table. The sensor is installed in the table. The sensor reads the current position of the table from the linear scale and outputs a signal indicative of the current position to the outside of the chamber. For that reason, a signal outputting cable extends from the sensor to the outside of the chamber.